George P. and Cynthia Woods Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, TX 77555, USA.
J Am Acad Dermatol. 2011 Nov;65(5):1023-31. doi: 10.1016/j.jaad.2010.09.735. Epub 2011 Jun 12.
Primary cutaneous amyloidosis (PCA) describes a heterogeneous group of cutaneous diseases characterized by amyloid deposition; this may manifest as macules, papules, or nodules, depending on the subtype involved. To date, relatively little is known about the process of amyloidogenesis in the skin; however, investigators recently have identified small amyloid species, known as oligomers, which give rise to large amyloid fibrillar aggregates.
The purpose of the current study was to identify small oligomers in patients with PCA using novel immunohistochemical techniques and to examine our findings in light of previous hypotheses of amyloid formation in these diseases.
Six cases of PCA were analyzed using Congo red, thioflavin S, and hematoxylin-eosin. We also analyzed these samples with the novel oligomer-specific conformational antibody I-11 to detect the small, misfolded protein oligomers. Semiquantitative analysis was performed on these samples to grade the amount of amyloid aggregates and oligomers detected in the skin samples with light and polarized microscopy.
In the cases examined, we detected intracellular oligomers in the basal cell layer of the epidermis and the surrounding cells in the dermis. We also were able to detect large aggregates of amyloid in our samples and to correlate the relationship of oligomers to amyloid aggregates in accordance with previous studies on cutaneous amyloidosis and other amyloid-related diseases.
Small sample size is a limitation.
PCA is an amyloid-related disease that likely follows a similar mechanism as other more intensively studied amyloid diseases.
原发性皮肤淀粉样变性（PCA）描述了一组以淀粉样物质沉积为特征的异质性皮肤疾病；根据所涉及的亚型，其可能表现为斑疹、丘疹或结节。迄今为止，人们对皮肤中淀粉样变性的过程知之甚少；然而，研究人员最近发现了称为低聚物的小淀粉样物质，这些低聚物会产生大的淀粉样纤维状聚集物。
本研究的目的是使用新的免疫组织化学技术在 PCA 患者中识别小的低聚物，并根据这些疾病中淀粉样形成的先前假说来检查我们的发现。
使用刚果红、硫黄素 S 和苏木精-伊红分析了 6 例 PCA。我们还使用新型低聚体特异性构象抗体 I-11 分析了这些样本，以检测小的、错误折叠的蛋白质低聚物。对这些样本进行半定量分析，以对皮肤样本中用亮场和偏光显微镜检测到的淀粉样物质聚集体和低聚物的量进行分级。
在检查的病例中，我们在表皮的基底细胞层和真皮周围细胞中检测到细胞内低聚物。我们还能够在我们的样本中检测到大的淀粉样物质聚集体，并根据对皮肤淀粉样变性和其他与淀粉样相关疾病的先前研究，将低聚物与淀粉样物质聚集体的关系进行关联。
样本量小是一个限制。
PCA 是一种与淀粉样物质相关的疾病，其发病机制可能与其他研究更为深入的淀粉样物质疾病相似。
